remove unused define
change deployment target to 10.8
drop old code and update project config
remove a pragma
add WebP and Portable Pixmap support

the WebP part is entirely dynamic. if the library is installed on your Mac (/usr/local/lib/libwebp.dylib) webp images will be rendered, if not they will be ignored.
If you have Pixelmator installed, its own QL plugin might get in the way, just remove the QuickLook folder within the Pixelmator.app package and relaunch the QL daemon.

For Portable Pixmap (ppm, pgm, pbm) you probably have to declare an UTI, easiest way is to use automator, see : http://superuser.com/questions/371892/osx-assign-extension-to-content-kind

For both these formats, Finder icons are generated and the preview window display dimension and file size like for the other format.
bump version, add webp UTIs
update readme
Do not resolv all symbol on dlopen() call
cosmetics